Sihpon Boxes?

Well I haven't posted in awhile, since a lot of things have been super crazy.  I'm leaving in about 6 days to go to London, and while looking for new places to live when I come back, and engagement rings, things have finally slowed down for a couple days before I leave.  My question is since im moving in about 3 weeks im interested in sumping my bio cube.  But I would like opinions on either drilling it or using a Eshopps Nano Siphon.  My idea is to either drill it or siphon it out of the 3rd Bio cube chamber and plus the original return outlet up, then drill a hole in the false wall in the 2nd chamber, and put a bulkhead. Then I would plumb the outlet into the bulkhead, so that I can keep using the chambers for water volume and so filtration.  The sump will most likely be a custom sump or a 7.5 gallon cube. 
Any Advice welcome.  If I need better descriptions let me know.